Newbie questions

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I have 2 LED 900W and 1 LED 300 W inside a 5x5x7 foot tent. Is that too much lighting. Even though they are LED it seems like too much heat inside. I use an exhaust fan and also have a oscillating fan inside. What is the best grow temperature inside a tent?

My next question is this. I saw an article that said roots need oxygen for good growth. Has anyone here tried putting an air hose connected to an aquarium air pump inside the growing pot? If so, did you see any positive improvement?

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Yes, pumping air into the root area does make a difference. It is a bit more difficult to pump air directly into a pot of soil; that's why the air-pot was invented; similarly, the air-pot allows air to get to the roots, but without a pump. Some growers use reinforced burlap sacks that drain water immediately away and therefore allow air in to the roots.

In hydroponics, oxygen in the feeding solution is a big plus. The oxygen can be introduced simply by having the solution drop through the air somewhere in its circulation stream, but even better by using an air-pump and an air-stone. When I run my hydroponics, I always have one air-stone in each solution-reservoir. When the plants are transferred to the flowering tent, I use ebb-N-flow hydroponics, and there, in addition to the air-stone in the reservoir, I also use an additional air-stone under each plant. All the air-pumps are on the same timer circuit as the lamps; ON when the lamps are on, and resting during the dark periods.

Lamps. You need different kinds of light for the Vegetative Phase as for the Flowering Phase. But, without your posting any pictures or describing the wavelengths and intensitiies produced by your lamps, it is difficult to offer any corrective advise. I assume that you do know about the photoperiod differences between Vegg and Flowering; that is a paramount concern that must be performed for normal photoperiod Cannabis.

Temps and relative humidity(RH). Yes, important. In Vegg, there are basically two phases. Phase 1 is germination & seedling (or cloning & seedling). Phase 2 is normal vegetation & growth. In the germ/cloning&seedling phase, the temps should lie somewhere between 24 to 28°C and the RH should lie between 50 to 75%. When the seedlings have produced their first true leaves (3 to 5 leaflets per leaf), then they have reached vegg&growth phase. Then, the best temps are around 23 to 26°C and the RH should be held between 45 to 65%. The Flowering Phase should begin with conditions similar to the Vegg&Growth Phase, but as the pre-flowerrs and flowers develop, the temps should be allowed to cool somewhat toward 20°C and the RH should be reduced to around 35 to 45%.

Please understand, the above are only target values that work well for me. Every grow is different, and depending on the configuration of your equipment, holding tightly to those values may not be possible. Or you may find that other values may work better for your equipment or even for the particular strain you are growing.

There is no need to panic for mild temperature or rH swings, but in general, wild swings should be avoided. Although in nature there is the natural temperature swing, the plant seems to grow best if the temperature can be stabilized both day and night around 25°C. The greatest danger from RH comes in the flowering phase; too high RH can lead quickly to mold that destroys your product, too low RH can create conditions favorable for pests such as caterpillers. Temps below 10°C and above 30°C can create enormous stress for the plant. Target pH(per-hydrous, acid-or-alkaline) for your feeding solutions in hydroponics is normally 5,8 in Vegg, rising to ~6,5 in flowering. Target pH for feeding solutions in soil is normally 6,2 in Vegg, rising to ~7,0 in flowering.

I suggest this often to new growers: Check-out the 9-part series in Youtube called "Mr. Green - I Grow Chronic". Each part is 15 minutes long. Informative and entertaining, he explains how to build a basic hydroponics set-up. This is the basis of my set-up, from which mine has further evolved. It works.

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